1. Field of the Invention
The present invention relates to a socket connector, and more particularly to a socket connector having a plurality of contacts, which includes a plurality of upper contacts engaging portions interlined with individual solder tails with different pitches.
2. Description of Related Art
With the trend toward miniaturization in electronic packages technology, contacts of sockets are arranged with high density, i.e. fine pitch arrangement. However, the existing soldering process can not match up with the socket with contacts with fine pitches.
U.S. publication No. 2007-0173138 issued to Lin et al. on Jul. 26, 2007 discloses a Land Grad Array (LGA) contact. The contact includes a base portion extending along a vertical direction, a contact portion extending upwardly from the base portion, a tail portion formed on a distal end thereof. The base portion connects the tail portion with a transitional portion, and the transitional portion comprises at least one twisted portion. The contact is integrally formed, and adjacent contact portions have a pitch that is equal to a pitch of adjacent tail portions. Thus, this contact can not be applied to the fine pitch arrangement.
U.S. Pat. No. 6,575,767 issued to Satoh et al. on Jun. 10, 2003 discloses a socket, used for testing an IC (integrated circuit) package, being applied to the fine pitch arrangement. The socket comprises a plurality of contact pins served as electrically connecting members. The contact pin comprises a spring function portion having elasticity, a contact portion which is formed on a top end side of the spring function portion and contacts with a terminal of the IC package, a conductive portion extending from an opposite side of the spring function portion, a mounting portion between the spring function portion and the conductive portion, and a connection leg portion extending from the conductive portion. A pitch of adjacent contact portions of the contact pins is smaller than that of the adjacent connection leg portions because of the conductive portions extending radially. However, the test socket contact is different to the LGA contact.
To get LGA contacts having different pitches between contact portions and tail portions, an improved contact arranged in the socket connector is required.